It’s a challenge only the bravest will tackle – more people have climbed Everest – and yet Australians have an undeniable pedigree when it comes to channel swimming. It took a pre-dawn swim in Sydney’s Botany Bay to find out why.

For Christian Renford, his presence in the water this morning is personal. At 49, he has spent much of his life immersed in sport. CEO of Athletics NSW, he’s a keen weekend swimmer. He is also Des Renford’s grandson, and this month he hopes to establish a record when he enters the water near Dover.

Should he reach France, he is likely to ­become the first third-generation swimmer to have crossed the Channel, following his famous grandfather, and then his uncle Michael Renford who completed the swim in 2007. But it’s not just his lineage that stands out. If he lasts the distance, Christian Renford, a middle-aged weekend freestyler from Sydney, will have made another mark, one that is more about ­resolve than genetics.